Biodiversity Flashcards
What is a cell wall
formed outside of the cell membrane and offer structural support to the cell. The structural support is provided by cellulose
What is middle lamella
outermost layer of the plant cell and acts like glue to stick adjacent plant cells together
It provides stability to the plant
What is plasmodesmata
Narrow threads of cytoplasm connect the cytoplasm of neighbouring plant cells
This allows substances to be transported between plant cells and facilitates cell to cell communication
What are pits
very thin regions of the cell wall in adjacent plant cells are lined up in pairs
This facilitates transport of substances between cells
What are chloroplasts
Larger than mitochondria, also surrounded by a double-membrane
Membrane-bound compartments called thylakoids containing chlorophyll stack to form structures called grana (singular = granum)
Grana are joined together by lamellae. Certain parts of photosynthesis occur in thylakoid membranes, while other parts happen in the stroma
What are amyloplasts
Small, membrane bound organelle containing starch granules.
They are responsible for storing starch
What is vacuole and tonoplasts
vacuole is a sac in plant cells surrounded by the tonoplast (selectively permeable membrane). Contains cell sap, which is a mixture of different substances
What are the functions of vacuoles
They keep cells turgid, which stops the plant from wilting
They can break down and isolate unwanted chemicals in plant cells
The tonoplast controls what can enter and leave
